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English definition of “lunacy”


noun [U]     /ˈluː.nə.sɪ/
stupid behaviour that will have bad results : It would be lunacy to try to climb the mountain in this weather . It was sheer lunacy spending all that money .Of unsound mindStupid and silly old-fashioned mental illness Of unsound mindStupid and silly
(Definition of lunacy noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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